Reg Kempton was the son of Richard Kempton and grandson of Charles henry Kempton. he in turn was the son in law of Henry Hall, craftsman glassmaker, who had an interest in both James Powell and son, and possibly Apsley Pellat/ Falcon Glass Works. Confirmation of this can found in Whitefriars Glass pub Museum of London by Wendy Evans, Catherine Ross, and Alex WErner on page 9. "Hall and Holmes" was the name of the glassworks circa 1786, and James Powell, a wine merchant, renamed it J. Powell & Sons, on purchasing it in 1834. Stephen Hall owned a Southwark glass house near Falcon steps, and was possibly the father of Henry Hall.
The glass works that became Whitefriars was called Hopton, Hanson & Stafford circa 1759 and Stephen hall was an executor of Carey Stafford.
I will coem back with more info on Reg, as I am studying in detail for a paper "The Kempton family" and there many glas works, and Reg appears to be the last glassmaker.